Opportunity for catch-up HPV vaccination in young women after first delivery Cristina Helena Rama, 1,2 Luisa L Villa, 3 Sonia Pagliusi, 4 Maria A Andreoli, 3 Maria C Costa, 3 Patricia Thomann, 5 Venancio A F Alves, 2 Adhemar Longatto-Filho, 6,7 Jose Eluf-Neto 2 ABSTRACT Background Early age at first delivery has been identified as a risk factor for high-risk HPV-type infection and cervical cancer development. Methods A cross-sectional study was carried out in a large public maternity hospital in Sa ˜o Paulo, Brazil. During June 2006 to February 2007, 301 women aged 15e24 years who gave birth to their first child were recruited between 43 and 60 days after delivery. Detection of HPV DNA in cervical specimens was performed using a standardised PCR protocol with PGMY09/11 primers. The association of selected factors with HPV infection was assessed by using a Generalised Linear Model. Results HPV DNA was detected in 58.5% (95% CI 52.7% to 64.0%) of the enrolled young women. The most common types of HPV found were: HPV16, HPV51, HPV52, HPV58 and HPV71. The overall prevalence of HPV types targeted by the HPV prophylactic vaccines was: HPV 16-12.0%, HPV 18- 2.3% and HPV 6 and 11 4.3%. In the multivariate analysis, only age (inversely, p for trend¼0.02) and smoking habits were independently associated with HPV infection. Conclusions The findings show that these young primiparous women had high cervical HPV prevalence, suggesting that this is a high-risk group for cervical cancer development. Nevertheless, 17.3% were positive for any of the four HPV types included in HPV vaccines (HPV6, 11, 16 or 18), with 13.3% positive for HPV 16 or 18 and only 1.0% having both vaccine related-oncogenic HPV types. Thus, young primiparous women could benefit from catch-up HPV vaccination programmes. INTRODUCTION Genital infection by oncogenic human papilloma- virus (HPV) is a necessary factor in the develop- ment of cancer of the cervix. 1 Worldwide, approximately 80% of around 500 000 of registered cervical cancer cases affect women in developing countries, and some 20 000 of them occur each year in Brazil. 2 Although the HPV family of viruses includes more than 100 different viral genotypes, 3 types 16 and 18 were identified in about 70% of cervical cancer cases. 4 Vaccines to prevent infections by high-risk viral genotypes 16 and 18 have been developed and have an excellent safety, immunogenicity and efficacy profile for the prevention of HPV infections, cytologic lesions and high-grade cervical lesions in women. 56 Ideally, HPV vaccination should take place before potential exposure to HPV through sexual contact, 7 because HPV L1 virus-like particle-based vaccina- tion has no therapeutic efficacy. 8 In some countries school vaccination programmes have been estab- lished as a strategy to vaccinate girls against HPV- associated diseases including cervical cancer. However, girls of lower socioeconomic status are more likely to drop out of school early. 9 In addition, vaccine coverage in adolescents can be low because they generally seek recommended preventive health services less frequently than other age groups. 7 Furthermore, early age at first delivery has been identified as a risk factor for cervical cancer development. 10 Therefore, opportunities for catch-up vaccination are valuable to improve coverage among the at-risk young female population. One such potential opportunity is offered by healthcare provided at first delivery; this approach would reduce the costs of reaching the ‘hard-to-reach’ adolescent groups by using infrastructures and procedures already in place in health services for offering novel vaccines. However, the success of catch-up vaccination of young women after first delivery depends on the baseline prevalence of high-risk genotypes 16 and 18 in this target group. So far, HPV infection rates have been shown to vary from 10.1% to 37.2% in pregnant women 11e13 in previous reports that used different HPV detec- tion techniques, distinct periods of pregnancy when samples were collected, and included partic- ipants in different age ranges, but did not focus on primiparous women. In particular, few studies in the postnatal period have reported vaccine-related HPV genotype prevalence in healthy young women. Therefore, the aim of this study was to deter- mine cervical type-specific HPV DNA prevalence and risk factors associated with HPV infection after the delivery of the first child among low-income young women in a public maternity hospital in the city of São Paulo, Brazil. MATERIAL AND METHODS Study population This cross-sectional study was carried out at Hospital Maternidade Leonor Mendes de Barros (HMLMB), one of the largest public maternity hospitals in São Paulo, Brazil. Primiparous women aged between 15 and 24 years who had been living in the metropolitan area of São Paulo for at least 6 months, and gave birth at this hospital after more than 32 weeks of gestation, were eligible for the study. They were enrolled at their postnatal visit, from June 2006 to February 2007. 1 Hospital Maternidade Leonor Mendes de Barros, Sa ˜o Paulo, Brazil 2 University of Sa ˜o Paulo School of Medicine, Sa ˜o Paulo, Brazil 3 Ludwig Institute for Cancer Research, Sa ˜o Paulo, Brazil 4 Ludwig Institute for Cancer Research, Lausanne, Switzerland 5 Qiagen do Brasil, Sa ˜o Paulo, Brazil 6 Life and Health Sciences Research Institute (ICVS), School of Health Sciences, University of Minho, Braga, Portugal 7 Pathology Division, Adolfo Lutz Institute Correspondence to Cristina Helena Rama, Hospital Maternidade Leonor Mendes de Barros, Av Celso Garcia, 2477, 03015-000 Belenzinho Sa ˜o Paulo-SP, Brazil; crisrama@usp.br Accepted 6 July 2009 Published Online First 19 August 2009 610 J Epidemiol Community Health 2010;64:610e615. doi:10.1136/jech.2008.086439 Research report